It might just be the rings which are 2.5mm further out. I think the Q factor is the same. GRX appers to be 151mm
Think to consider. Is the spacing between the rings the same on mtb and grx? Is the chainline the same?
You're right, I have to consider chainline, not Q factor
@Cosme started
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It might just be the rings which are 2.5mm further out. I think the Q factor is the same. GRX appers to be 151mm
Think to consider. Is the spacing between the rings the same on mtb and grx? Is the chainline the same?